An interesting concept:
A company releases a CD with lots of commercial programs and eval versions for them on it, in an encrypted way.
They give the CD away on events (like the CeBIT), and the idea is that people wanting to use one of these programs just call the included phone number and get a (personalized) key to decrypt the installation files.
However, they didn't factor in the CCC hackers (which was still in its infancy back then, not these huge events that they're known for nowadays). They found out that, apparently, the decryption codes were just 6-round DES with an 8-bit key that could easily be brute-forced, and they did so before the first day of the CeBIT was over...
Needless to say that this was the first AND last CD that this particular company offered ;-)
Interestingly I couldn't really find much about the CD (or the codes) on the internet today, it seems everything has just vanished except for 2 press articles and 2 Google groups posts.
I have included a file that contains the keys, but I think you need a patched/hacked crypt.dll file as it somehow factors in the volume ID of the harddisk, so no decryption out-of-the-box ;-)
More info (in German):
http://www.offiziere.ch/trust-us/ds/47/004_yellow_point_story.htm
http://www.spiegel.de/spiegel/print/d-13684190.html
http://www.spiegel.de/spiegel/print/d-13684138.html